INN3675C
InnoSwitch3-CP with 750V MOSFET, synchronous rectification, and FluxLink feedback for efficient 35W designs
Product Overview
Description
The INN3675C is a member of the InnoSwitch3-CP family, offering exceptional performance for compact power supply designs up to 35W.
Featuring an integrated 750V power MOSFET, synchronous rectification controller, and FluxLink isolated feedback technology, this IC eliminates the need for an optocoupler while maintaining excellent output regulation.
The device includes comprehensive protection features including OVP, OCP, OTP, and brown-in/brown-out protection, making it ideal for high-reliability applications.
Product Series
INN
Primary Application
High-efficiency adapters
Key Features
- Integrated 750V power MOSFET
- Synchronous rectification controller
- FluxLink isolated feedback technology
- CCM/QR flyback controller
- Comprehensive protection features
- Excellent EMI performance
Specifications
| Power Rating | Up to 35W |
|---|---|
| Input Voltage | 85-265V AC |
| MOSFET Voltage | 750V |
| Efficiency | Up to 94% |
| Standby Power | <30mW |
| Package | InSOP-24D |
Applications
High-efficiency adapters
Electronic system design
Appliance power supplies
Electronic system design
Industrial auxiliary power
Industrial automation and control
LED lighting drivers
Motor drive and control systems
FAE Expert Insights
"In my 10 years of experience with AC-DC designs, the InnoSwitch3 family is significant advancement in flyback converter technology. The integration of synchronous rectification with primary-side control through FluxLink technology eliminates the traditional optocoupler, which is often a reliability concern in power supplies. I particularly recommend the INN3675C for designs where both efficiency and compact size are critical. The built-in protection features and excellent EMI characteristics reduce design time and BOM cost. For high-volume production, the consistent performance across temperature and line conditions ensures reliable operation."
Excellent efficiency and reliability with integrated synchronous rectification
— Michael Chen, BeiLuo
Frequently Asked Questions
What is the maximum output power of INN3675C?
The INN3675C can deliver up to 35W of continuous output power in a typical flyback configuration with adequate heatsinking. The actual maximum power depends on several factors including input voltage range, output voltage, thermal design, and ambient temperature. For universal input applications (85-265V AC), the typical maximum is 35W. For high-line only applications (185-265V AC), higher power may be achievable. Always refer to the datasheet and use PI Expert software for accurate power capability calculations based on your specific design parameters.
Use PI Expert software to verify power capability for your specific design conditions, or contact our FAE team for thermal design guidance.
How does FluxLink technology work?
FluxLink is Power Integrations' proprietary isolated feedback technology that eliminates the need for an optocoupler. It works by magnetically coupling the feedback signal from the secondary side to the primary side using the transformer itself. A small winding on the transformer transmits the feedback information, providing fast and accurate output voltage regulation while maintaining galvanic isolation. This technology offers several advantages: 1) Higher reliability by eliminating the optocoupler which degrades over time, 2) Faster transient response, 3) Better cross-regulation in multi-output designs, 4) Reduced component count and PCB area.
Consider FluxLink technology for designs requiring high reliability and long operational lifetime, such as industrial and automotive applications.
What protection features are built into INN3675C?
The INN3675C includes comprehensive protection features: 1) Overvoltage Protection (OVP) - shuts down the converter if output voltage exceeds safe limits, 2) Overcurrent Protection (OCP) - limits peak current to protect the power MOSFET, 3) Overtemperature Protection (OTP) - shuts down at excessive junction temperature with hysteresis, 4) Brown-in/Brown-out Protection - prevents operation at unsafe input voltages, 5) Output Overload Protection - hiccup mode operation during sustained overload, 6) Short-circuit Protection - automatic restart after fault removal. These protections ensure safe operation under abnormal conditions and protect both the power supply and the load.
The built-in protection features make INN3675C suitable for applications requiring high reliability and safety compliance.
How do I design with INN3675C?
Designing with INN3675C is streamlined using Power Integrations' design tools: 1) Use PI Expert Online software for automated design - input your specifications and get optimized transformer parameters and component values, 2) Download reference designs from the Power Integrations website for similar applications, 3) Use the evaluation board (RDK-XXXX) for prototyping and testing, 4) Follow the layout guidelines in the datasheet for optimal EMI and thermal performance. Key design considerations include: transformer design (PI Expert provides specifications), snubber circuit design, output filter capacitor selection, and thermal management. Our FAE team can review your design and provide optimization suggestions.
Start with PI Expert software for automated design, then contact our FAE team for design review before prototyping.
What is the typical efficiency of INN3675C?
The INN3675C achieves typical efficiency up to 94% depending on the operating conditions and design optimization. Key factors affecting efficiency include: 1) Output voltage and current - higher voltage outputs generally achieve better efficiency, 2) Transformer design - proper core selection and winding design minimizes losses, 3) Synchronous rectification - the integrated SR controller significantly improves efficiency compared to diode rectification, 4) Operating frequency - optimized switching frequency balances efficiency and size. For a typical 12V/2.5A output design, efficiency of 92-94% can be achieved at full load with universal input voltage.
Use PI Expert software to estimate efficiency for your specific design parameters and optimize for maximum efficiency.